It doesn't really matter. The recovery rate of mechanical broadheads is a little bit higher but negligible since the rates are overall extremely good (82 % fixed vs 91 % mechanical). So, if you are used to mechanical broadheads and can afford them, I would recommend to go with them. If you aren't used to them (normally shooting with fixed broadheads), I would recommend to grab the fixed ones.
Mechanical vs. Fixed-Blade: Stratified by broadhead type (including both compound bows and crossbows), hunters using fixed-blade broadheads recovered 82 percent of their deer (874 recovered out of 1,066 hit). Hunters using mechanical broadheads recovered 91 percent of their deer (209 out of 230 hit). Note: Total numbers of deer are lower for mechanicals because they have only been approved for use on the base since 2007, although the majority of deer shot since then were shot with mechanicals. More on that shortly.
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All types of bows and broadheads are capable of producing extremely high recovery rates, but you cannot overlook the education and proficiency requirements for these hunters, and that they reported an average shot distance of less than 20 yards. The hunters on this base are clearly selective and careful about their shots, which contributed to the high recovery rates. Regardless of equipment, we all share a responsibility to practice regularly and choose the right shots. The choices you make before the arrow is released are just as important as the clinical physics of broadhead performance.
Just make sure that your tips are more than two bladed.
